Stabilizing-spring for bobbins.



E. W. CORCORAN 8.: F. W. PUND.

STABILIZING SPRING FOR BOBBINS.

APPLICATION FILED APR. [7. I917.

Patented Aug. 13, 1918.

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UNITED STATES PATENT OFFICE.

EDWARD W. GORCORAN AND FREDERICK W. PUND, OF CINCINNATI, OHIO.

Specification of Letters Patent.

Patented Aug. 13, 1918.

Application filed April 17, 1917. Serial No. 162,695.

1 To all whom 2'2. may concern:

Be it known that we, EDWARD W. Conco- RAN and FREDERICK W. PUND, citizens of the United States, residing at Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Stabilizing-Springs for Bobbins, of which the following is a specification.

Our invention relates to new and useful improvements in springs, the primary object of our invention being the provision of a novel type of stabilizing spring to be used on various kinds of machines for the purpose of reducing friction, stationary, rotary and otherwise, as in bobbin cases on sewing machines.

A still further object of our invention resides in providing a spring for the above described purposes which may be formed from a single length of resilient wire, the ends of which will be joined when the spring is finished so that an endless body in the form of a frusto-conical surface is provided comprehending a plurality of resilient and opposed loops extending radially of the body.

Another object which we have in view is the provision of a spring which is particularly adapted for use in bobbin cases to stabilize and properly hold the thread bobbin and to assist in the removal of the bobbin core after the thread has beenused.

With these and other objects in view, our invention will be more fully described, illustrated in the accompanying drawings, and then specifically pointed out in the claims which are attached to and form a part of this application.

In the drawings:

Figure 1 is a perspective view of a conventional form of bobbin case, thread bobbin and our improved spring, showing the method of assembling the parts;

Fig. 2 is a diametrical. sectional View of the bobbin case, thread bobbin and spring 1n assembled position.

Corresponding and like parts are referred to in the following description and indicated in all the views of the drawings by the same reference characters.

As will be readily appreciated by reference to Figs. 1 and 2 of the drawings, our improved spring 10 is formed from a single length of resilient wire of suitable metal and weight. This wire is successively bent and rebent upon itself to provide a spring in the shape of the frustum of a cone and cons1st1ng of a plurality of inwardly opening loops a, the sides I) of adjacent inwardly opening loops being crossed, whereby a series of closed loops 0 are provided. These open loops at are relatively narrow in proportion to their length and their intermediate or outer portions lie in a common circle, while the closed loops 0, which are relatively small, have their intermediate or inner portlons lying in a common circle concentric with the circle in which the intermediate portions of the open'loops lie. The inclinat1on of the loops to the horizontal may be varied at willin'the construction of the spring. Preferably, the free ends of the wire are twisted or otherwise connected, as shown at d, the joined ends forming in effect one of the closed loops of the spring.

The above described spring, we have found, is particularly adapted for use as a stabilizing spring in bobbin cases and for th1s reason we have illustrated it in connection with a conventional bobbin case 11 including the cylindrical body portion 12 closed at one end by the head 13 and formed centrally with the tubular pin or spindle 14:. As this bobbin case is of conventional type no further explanation of it is believed necessary. In connection with this bobbin case we have shown a removable commercial thread bobbin 15 formed upon the usual. bobbin core 16 adapted for application about the spindle 14. Preferably, a guard disk 17 of relatively thin metal is formed with a hub 18 for insertion in the outer end of the bobbin core so that the disk will be held in place to protect the thread of the bobbin. In the use of the spring, the spring is inserted in the bobbin case with its larger end in engagement against the inner face of the head when the thread bobbin is applied in the usual manner to engage against the smaller end of the spring. Preferably, the spring should be so proportioned that its outer or larger end will engage or substantially engage against the inner face of the body 12 of the bobbin shell although,.due to the particular construction of the spring, this is not essential as the spring may be compressed either through spreading of the outer open loops and consequent increase in diameter of the spring, or through moving together of the inner closed loops and corresponding reduction of diameter of the inner or smaller end of the spring. Obviously, the spring will hold the thread bobbin steady and under proper tension as it has a wide circumferential bearing engagement with the head of the bobbin shell and also a circumferential engagement with the thread bobbin. lVhen the thread bobbin is released from the bobbin shell, the spring will assist in forcing the empty bobbin core from the shell.

Although we have illustrated and described the spring indetail and have specifically set forth its ,use in bobbin cases it will be understood that we reserve the right to employ the spring for any purpose for which it may be found eflicient and also the right to make any changes in the vconstruetion of the spring itself which may fall within the scope of the claims.

Although we have illustrated the spring in connection with a Singer central bobbin case, it will be understood that it may be employed with any type of bobbin case for which it is adapted, such as the \Vheeler and lVilson machine bobbin case and that the spring will be equally effective with various styles of bobbins having either large or small center cores and guard disks or not.

Having thus described the invention, what is claimed as new is: I

l. A spring formed from a single length of resilient wire successively bent and rebent upon itself to provide a series of outer open bends, the adjacent sides of adjacent bends crossing each other to provide a corresponding inner series of closed loops and the ends of the wire being joined whereby an annular resilient body is provided, the surface of Which is lnclined to its axis.

2. A spring formed from a resilient element bent and rebent upon itself to produce anannular body consisting of resilientloops with the inner portion of the body in a plane spaced from that of the outer portion.

3. A spring formed from a resilient elementbent and rebent upon itself to produce an annular body consisting of resilient loops with the inner portion of the body in a plane spaced from that of the outer portion, the loops being radially disposed.

A spring formedfrom a resilient element bent and rebent upon itself to producean ann tlar body consisting of resilient loops with the inner portion of the body in a plane spaced from that of the outer portion the loops being radially disposed and compressible and expansible.

5. A spring foigmedfroin a length of resilient wire looped upon itself into an annular body the loopsof which extend at an inclination tothe axis and having its ends a.- i FltEDEltIGK W. ru n Copies of this patent may be obtained for five cents each, byagiflre,8, 11 %the CQWQiSfilQlLer of Patents Was n n, 11 .9) 

